Water-soluble monomers are ordinarily used as starting materials for polymers in order to impart water solubility or water dispersibility to a polymer. Among water-soluble monomers, polyalkylene glycol-type monomers are useful industrial starting materials generally employed in industry as water-soluble monomers and, for example, when copolymerized with a carboxylic acid (salt)-type monomer, yield polymers that can be used in a wide variety of applications. Such water-soluble polymers are well suited for use as starting materials, for example, for dispersing agents, detergent compositions, scale removers, cement additives, thickeners, and so forth. Among such water-soluble monomers, polyalkylene glycol-type monomers that have a particular functional group in combination with a polymerizable double bond are receiving attention and are under development. Active investigations are underway into the functionalities that are conferred by the introduction of functional groups into the polymers obtained from such monomers.
With regard to the production of water-soluble monomer having a particular functional group, a synthetic scheme must be devised here for introducing the particular functional group in combination with the polyalkylene glycol chain, which exhibits properties such as water solubility, and several synthetic procedures have been disclosed.
For example, within the sphere of conventional processes for the synthesis of polyalkylene glycol-type monomers that have a particular functional group, and more specifically as a process for producing a polyalkylene glycol-type compound that has a specific structure and contains the carboxyl group and/or a carboxyl group salt, a process has been disclosed in which a compound provided by the addition of an alkylene oxide on an unsaturated alcohol is reacted with epichlorohydrin and the resulting reaction product is reacted with a compound that contains a particular reactive group and the carboxyl group (refer, for example, to Patent Document 1).
In addition, monomers with particular structures (refer, for example, to Patent Documents 2, 3, and 4) have been disclosed as compounds that have the same structure as the aforementioned reaction product obtained by the reaction of epichlorohydrin and a compound provided by the addition of an alkylene oxide on an unsaturated alcohol; these monomers are disclosed, for example, as a monomer component of polyether copolymers. Moreover, a monomer having a particular structure (refer, for example, to Patent Document 5) has been disclosed as a monomer component for synthesizing a specific polyether polymer having an oligooxyethylene side chain.
On the other hand, amino group-containing polymers obtained by the polymerization of amino group-containing monomer and cationic polymers obtained by the polymerization of cationic group-containing monomer, which is a type of water-soluble monomer that has a particular functional group, have heretofore been used in a broad range of fields, e.g., coagulants, flocculants, printing inks, adhesives, detergent and cleanser additives, soil conditioners (improvers), flame retardants, shampoos and hair sprays, additives for soaps and cosmetics, anion-exchange resins, dye mordants and auxiliaries for fibers and photographic films, pigment spreading agents in paper manufacturing, paper-reinforcing agents, emulsifying agents, anticorrosion agents, softeners for textiles and paper, and additives for lubricating oils.
For example, polymers having a main chain derived from a particular monomer component have been disclosed, and it has been disclosed that a copolymer from a hydrophobic comonomer and diallyldimethylammonium chloride, which is a typical cationic monomer, can be used as a laundry additive for preventing dye migration and/or dye bleeding from fibers (refer, for example, to Patent Document 6). In addition, specific modified alkyleneimine-type polymers having an alkyleneimine structural unit have been disclosed, and it has been disclosed that such polymers exhibit an excellent performance in applications such as detergents and cleansing agents (refer, for example, to Patent Document 7). It has been disclosed that a high detergency is shown by a detergent composition that contains an alkanolamine, a polymer compound containing a structural unit derived from a monomer having a vinylpyridine moiety, and prescribed amounts of a nonionic surfactant and a non-soap anionic surfactant (refer, for example, to Patent Document 8). In addition, an amino group-containing monomer has been disclosed as a special siloxane present in a composition (refer, for example, to Patent Document 9).
Sulfonic acid group-containing polymers yielded by the polymerization of a sulfonic acid group-containing monomer, which is one type of water-soluble monomer having a particular functional group, have also been used in a broad range of fields, e.g., water-treatment agents, detergent builders, detergent compositions, dispersing agents, and cleansers.
For example, polyalkylene glycol-type compounds have been disclosed that have in the molecule a terminal double bond and a particular structural moiety that contains a sulfonic acid group, and it has been disclosed that such polymers exhibit elevated properties in water-based applications such as dispersing agents and detergent builders (refer, for example to Patent Document 10).
In addition, polyalkylene glycol-type polymers produced from a polyalkylene glycol-type monomer that contains a hydrophobic moiety, which is one type of water-soluble monomer having a particular functional group, are known to exhibit—due to their ability to adsorb hydrophobic substances through hydrophobic interactions coupled with the dispersing capacity of the polyalkylene glycol chain—properties such as an excellent ability to disperse hydrophobic particles, an excellent anti-soil redeposition performance for hydrophobic soils, and an excellent detergency, and thus are known to be very suitable for use in various applications, e.g., detergent compositions, fiber-treatment agents, water-treatment agents, and various dispersing agents for, e.g., pigments. The following, for example, have been disclosed as such monomers: polyalkylene glycol-type monomer that has a polyalkylene glycol chain and a polymerizable double bond originating from allyl glycidyl ether and that has a hydrophobic moiety in the polyalkylene glycol chain and/or at a terminal of the chain, and polyalkylene glycol-type monomer that has a polyalkylene glycol chain and a polymerizable double bond originating from isoprenol, allyl alcohol, or methallyl alcohol and that has a hydrophobic moiety originating from C1-20 glycidyl ether in the polyalkylene glycol chain and/or at a terminal of the chain. A process has been disclosed for producing these polyalkylene glycol-type monomers in which a C1-20 glycidyl ether is reacted with an adduct provided by the addition of a polyalkylene glycol chain to isoprenol, allyl alcohol, or methallyl alcohol (refer, for example, to Patent Document 11).
The properties required of a laundry additive (detergent additive) have been changing over the last few years due to rising consumer awareness with regard to environmental issues. Thus, the use of residual bath water for doing laundry has become an established laundry practice with the goal of water conservation. This results in problems such as the attachment of soil components present in the residual bath water to fabric during laundering and the concentration of hard water components due to reheating of the bath, and as a consequence there are now even more demanding requirements on the anti-gelation performance and the capacity to capture the metal ions, e.g., the calcium ion, magnesium ion, and so forth, present in the water that cause a deterioration in the detergency, and on the capacity to inhibit the re-attachment of soil components to fabric during the laundry process (“anti-soil redeposition performance”), even in the presence of higher hardnesses. Moreover, the number of households that use a drum washing machine is increasing as consumers seek to conserve water and reduce the amount of waste water. A better capacity to inhibit dye transfer (anti-dye transfer performance) is then required since doing laundry under water-conserving conditions makes fabric-to-fabric dye migration during the laundry process an even bigger problem than before.
Furthermore, the detergents that are undergoing an increase in current demand due most importantly to their suitability for use in drum washing machines are liquid detergent concentrates in which the content of liquid detergent, and particularly surfactant, is 50% or more. As a consequence, a detergent additive must be well adapted for incorporation in such a liquid detergent concentrate and detergent additives must therefore exhibit a better compatibility with surfactants than in the past.    [Patent Document 1] Japanese Patent Application Laid-open No. 2010-132814 (pages 1-2, 15-17)    [Patent Document 2] European Patent Application No. 838,487 (pages 1-2)    [Patent Document 3] Domestic Republication of PCT International Application WO 98/007772 (page 47)    [Patent Document 4] Domestic Republication of PCT International Application WO 97/042251 (page 50)    [Patent Document 5] Japanese Patent Application Laid-open No. S63-241026 (pages 1-2)    [Patent Document 6] WO 04/056888 (pages 6-7, 37)    [Patent Document 7] Japanese Patent Application Laid-open No. 2005-170977 (pages 2-3)    [Patent Document 8] Japanese Patent Application Laid-open No. 2008-1770 (pages 2-3)    [Patent Document 9] WO 97/32475 (page 19)    [Patent Document 10] Japanese Patent Application Laid-open No. 2008-303347 (pages 2, 8)    [Patent Document 11] Published Japanese Translation of PCT Application No. 2009-510175 (pages 2, 11)
Based on the current circumstances as described above, various investigations have been carried out into polymers that can also be used in the previously described detergent compositions and into water-soluble monomers that are starting materials for such polymers. For example, investigations have been carried out, as in the previously indicated Patent Document 1, into processes for producing water-soluble polyalkylene glycol-type monomers, but there was still room for additional improvements in order to achieve even better use as a polymerization starting material for various polymers.
Thus, a water-soluble monomer preferably has a polymerizable double bond at a terminal and suitably also has a particular functional group at another terminal. This serves to secure polymerizability for the monomer while positioning the particular functional group, once the polymer has been formed, at a terminal of the polymer side chain and thus has the advantage of a facile manifestation of properties deriving from the particular functional group.
Investigations have thus been carried out into the production of water-soluble monomers that have such a structure. However, when a water-soluble polymer was produced by polymerizing a water-soluble monomer in the form of a polyalkylene glycol-type monomer that had a polymerizable terminal double bond and a functional group at another terminal and that exhibited water solubility due to the polyalkylene glycol chain, it was found that gelation ended up occurring and the yield of the water-soluble polymer was lowered.
The production of such a polyalkylene glycol-type monomer requires an intermediate that is a precursor for the monomer, and it was discovered that this intermediate influences the polymerization properties of the obtained water-soluble monomer and that problems that produce defects during production of the water-soluble polymer reside here.
In addition, as noted above, despite the various water-soluble polymers that have heretofore been reported, these have been concerned with the properties for the water-based applications described above, and it cannot be said, for example, that they can necessarily fully satisfy the most recent demanding requirements, e.g., the needs of users for polymers that demonstrate a high anti-dye transfer performance when used as a detergent additive, and there has been room for additional improvements with regard to polymers that can respond to these new needs and exhibit higher property levels and are well-adapted for applications such as detergent additive applications.
Otherwise, investigations as in the previously indicated Patent Document 11 have been carried out on processes for producing a polyalkylene glycol-type monomer that contains a hydrophobic moiety. However, when the production process disclosed in Patent Document 11 is used, secondary products are produced when two or more molecules of the C1-20 glycidyl ether react with the monomer having a polyalkylene glycol chain and a polymerizable double bond, which results in the problems of a diminished reaction selectivity and a reduction in the purity of the obtained polyalkylene glycol-type monomer. And as a result, the properties of the polyalkylene glycol-type polymer yielded by the polymerization of the thusly obtained polyalkylene glycol-type monomer may not be satisfactorily manifested.